真空预压条件下的砂井地基Hansbo固结解

HANSBO′S CONSOLIDATION SOLUTION FOR SAND-DRAINED GROUND UNDER VACUUM PRELOADING

结合真空预压时的实际边界条件,引入负压沿砂井的线性衰减分布模式,将Hansbo砂井地基径向固结理论推广到真空预压(负压)情况,并与现有的董志良解及Indraratna解进行比较,以验证其正确性。结果表明,3种解析解得到的任意时刻径向固结度Ur的关系为:本文解>董志良解>Indraratna解。当时间因素Th≤0.5时,三者间相对误差较大,但绝对误差很小,随着时间的增长(Th>0.5),误差逐渐减小。本文解较Indraratna解更接近较为严密的董志良解,且本文解形式简单,利于工程推广应用。当不考虑井阻作用时,3种解析解均可简化为负压条件下的无井阻固结Hansbo解。

The Hansbo′s consolidation theory for sand-drained ground was extended to the condition of vacuum preloading,in which the distribution pattern of negative pressure along the sand drain was considered,and then it was compared with the existing Dong Zhiliang′s solution and Indraratna′s solution to verify its correctness. The results show that the relation of the radial consolidation degree Ur obtained by the three analytical solutions is that the new solutionDong Zhiliang′s solutionIndraratna′s solution. When Th≤0.5,the relative error among the three analytical solutions is relatively large,but the absolute error is small;and then the error decrease gradually with time（Th0.5）. The new solution is more close to Dong Zhiliang′s solution than Indraratna′s solution;and its form is simple,which is advantaged to engineering practice. When the well resistance of sand drain isn′t considered,the three analytical solutions can be simplified to Hansbo′s solution under vacuum preloading.